WO 2005/023690 A1 describes a method for reducing register errors, i.e., errors in the relative positioning of two image points to be imprinted successively on the web, wherein a deformed or deformable roller is provided at the intake to the respective printing couple. In addition, a register adjustment can be carried out by increasing a temperature between two successive printing nips (printing couples) by means of a dryer for shrinkage, or by applying moisture, for example, in the form of saturated vapor, for expansion.
U.S. Pat. No. 4,404,906 A describes a device for controlling fan-out, i.e., web expansion caused by the penetration of moisture during the printing process, wherein the web to be imprinted is guided over a bowed roller upstream of the first printing couple.
EP 1 826 002 A2 discloses a printing press comprising at least one printing unit, a dryer positioned downstream thereof, a cooling roller assembly, a re-dampening device, and a folding unit, wherein for controlling web tension, the speed ratio of a positively driven cooling roller in relation to a positively driven main nipping roller located upstream in the web path can be adjusted.
DE 94 19 702 U1 describes a device for preventing the formation of waves in a printing press, wherein a web is deflected one or more times, each time in an opposite direction of curvature, by a spreading roller, immediately before said web reaches the first cooling roller of a cooling unit.
DE 30 22 557 A1 discloses a cooling system for a web-fed rotary printing press having a substantially vertical web path. To prevent crease formation, it is proposed, rather than using known spreading rollers upstream of nipping units, to embody at least one cooling roller of the cooling unit as having a diameter which increases substantially steadily from the center outward.
U.S. Pat. No. 6,058,844 A discloses a web-fed rotary printing press having a vertical web path, wherein in one embodiment, the cooling rollers are embodied with a reduced radius toward the outside, and in another embodiment, bowed spreading rollers are arranged in the cooling unit in addition to the cooling rollers. In the latter embodiment, the degree of web wrap is the determining factor for the spreading effect. To correct crease formation, the arc of the spreading roller is pivoted into the web plane.
U.S. Pat. No. 6,250,220 B1 discloses a spreading roller in a printing press having a substantially vertical web path, wherein upstream of the cooling rollers, a spreading roller is provided, which can be alternatively pivoted into the web path for production operation, or pivoted out of the web path for set up.
WO 2007/020288 A1 discloses a printing press that comprises a first printing tower with a first printing unit having an offset printing couple for printing one or both sides of a first web, a dryer arranged downstream of the first printing unit in the web path, along with a former structure having a fold former through which the first web passes and a nipping roller positioned upstream of the fold former. Said printing press also comprises a second printing tower with a second printing unit having an offset printing couple for printing one or both sides of a second web, wherein means for guiding the second web are provided, via which the second web can be or is guided, together with the first web, to the at least one fold former, without passing through a dryer, or at least without passing through an activated dryer.
EP 1 547 772 A1 discloses a sheet-fed offset printing press. The print substrate is first imprinted in corresponding printing couples using oil-based offset inks, and is then coated in a printing couple downstream using oil-based flat varnish that contains silicone varnish.
EP 1 518 805 A2 relates to a method for determining production-relevant material properties and a method for pre-adjustment. In the printing press, information regarding expansion characterization and moisture sensitivity of the infed web, etc., can be determined from corresponding variations, and corresponding pre-adjustment values for web tension can be determined.